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clear that the chief radiological concern at early times following an explosion
will be those of total body radiation from gamma rays and skin irradiation
from beta emitters.
Except for the development of thyroid abnormalities and slight growth retardation
in some exposed children, overt evidence of late effects of exposure have been
minimal in the Marshallese.
General health and disease incidence have remained
about the same in the exposed and unexposed populations with no clear cut effects
noted on mortality, birth rate, longevity, aging, incidence of malignancy and
degenerative diseases or opacities of the lens.
A few other positive Findings
appear to be associated with their exposure such as an increase in miscarriages
and stillbirths in the exposed women during the first 4 years after exposure, a
lag in complete return of peripheral blood counts to the unexposed levels during
the decade after exposure and the persistence of a low level of chromosomal
aberrations at 10 years post exposure.
The most important late findings have
had to do with growth and development in the exposed children and the development
of thyroid abnormalities.
Slight retardation of growth has been noted mainly in
the boys exposed at less than 12 years of age first noted a few years after
exposure.
Since 9 years post exposure thyroid nodules have developed in 17 cases
and thyroid deficiency in 2 cases({all but.3 of these were in children exposed
at less than 10 years of age).
These effects are believed to be related to
injury of the thyroid gland from exposure to radioiodines and gamma radiation
at the time of the fallout.
The detection of thyroid damage was hindered
by its slow onset and due to the fact that the true PBI levels were masked
due to the finding of elevated levels of iodoprotein in the Marshallese people.
Thyroid surgery revealed that all nodules were benign except for 1 exposed adult
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